1. Field
The present disclosure generally relates to fabrication of composite laminates, and deals more particularly with a method, device and apparatus for vacuum forming a composite laminate.
2. Background
Composite laminate stiffeners are sometimes required to have complex contours tailored to particular applications. For example, in the aircraft industry, composite laminate stringers used to stiffen aircraft skins are sometimes contoured in one or more planes in order to match changes in the skin geometry often found in aerodynamic fuselages and airfoils.
Layup and forming of composite laminate stiffeners having complex contours can be challenging because composite prepreg material may bridge or wrinkle in the areas of contours. In order to minimize these conditions, composite laminate structural stiffeners such as stringers are usually laid up by hand; however, hand layup of stiffeners is both labor-intensive and time-consuming, and therefore expensive. Automation of forming and compacting of contoured composite stiffeners may require complex, heavy and/or expensive equipment.
Accordingly, there is a need for a method, device and apparatus for forming and compacting contoured composite stiffeners such as composite laminate prepreg stringers, that reduce part non-conformities and touch labor. There is also a need for a method, device and apparatus of the type mentioned above which obviate the need for specialized, heavy forming equipment, and rely on conventional vacuum diaphragms to develop the necessary forming pressures.